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1.
Artigo em Inglês | MEDLINE | ID: mdl-38619955

RESUMO

In radial basis function neural network (RBFNN)-based real-time learning tasks, forgetting mechanisms are widely used such that the neural network can keep its sensitivity to new data. However, with forgetting mechanisms, some useful knowledge will get lost simply because they are learned a long time ago, which we refer to as the passive knowledge forgetting phenomenon. To address this problem, this article proposes a real-time training method named selective memory recursive least squares (SMRLS) in which the classical forgetting mechanisms are recast into a memory mechanism. Different from the forgetting mechanism, which mainly evaluates the importance of samples according to the time when samples are collected, the memory mechanism evaluates the importance of samples through both temporal and spatial distribution of samples. With SMRLS, the input space of the RBFNN is evenly divided into a finite number of partitions, and a synthesized objective function is developed using synthesized samples from each partition. In addition to the current approximation error, the neural network also updates its weights according to the recorded data from the partition being visited. Compared with classical training methods including the forgetting factor recursive least squares (FFRLS) and stochastic gradient descent (SGD) methods, SMRLS achieves improved learning speed and generalization capability, which are demonstrated by corresponding simulation results.

2.
J Agric Food Chem ; 72(14): 7794-7806, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38561246

RESUMO

To investigate the effects of fertilization methods and types on wheat rhizosphere microorganisms, macroelement (N, K) and microelement (Zn) fertilizers were applied on wheat by foliar spraying (FS) and root irrigation (RI) methods in a field experiment. The results indicated that fertilization methods and types can have significant impacts on the diversity and structure of rhizospheric microorganisms in wheat. The application method produced more significant effects than the fertilizer type. RI-N played a more important role in improving the wheat yield and quality and affected the changes in some nitrogen-fixing bacterial communities. Finally, eight strains of bacteria belonging to Pseudomonas azotoformans and P. cedrina showed positive effects on the growth of wheat seedlings. Overall, our study provides a better understanding of the dynamics of wheat rhizosphere microbial communities and their relation to fertilization, yield, and quality, showing that plant growth-promoting rhizobacteria with nitrogen fixing may be a potential approach for more sustainable agriculture production.


Assuntos
Microbiota , Triticum , Rizosfera , Nitrogênio/análise , Fertilizantes/análise , Fertilização , Solo/química , Microbiologia do Solo
3.
Chem Sci ; 15(13): 4881-4889, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38550680

RESUMO

Simultaneously enhancing the quantum yields and luminescence lifetimes of organic persistent room temperature phosphorescence (RTP) molecules is a priority in the organic photonic area, but it remains a formidable challenge. Here, an effective strategy was proposed to improve both quantum efficiencies and emission decay times for phosphorescent triphenylphosphine salts. This approach involves integrating an electron donor unit into a triphenylphosphine salt via an alkyl chain. This structure facilitates an intermediate through-space charge transfer excited state, which enhances the intersystem crossing process to boost RTP performance. Moreover, the electron donor moiety contributes additional triplet excitons to the triphenylphosphine salts through triplet-to-triplet energy transfer, substantially increasing the population of triplet excitons. Specifically, compared to butyl(naphthalen-1-yl) diphenylphosphonium bromide (Φphos. = 4.9% and τ = 255.79 ms), (2-(9H-carbazol-9-yl)ethyl)(naphthalen-1-yl)diphenylphosphonium bromide demonstrates a higher phosphorescence quantum yield of 19.6% and an extended emission lifetime of 800.59 ms. This advancement lays the groundwork for developing high-performance organic RTP materials, unlocking new possibilities for advanced photonic applications.

4.
Adv Mater ; 36(7): e2306834, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37633310

RESUMO

Long-lived room-temperature phosphorescence (RTP) of organic materials holds a significant potential for optical information. Circularly polarized organic ultralong room-temperature phosphorescence (CP-OURTP) with extremely high dissymmetry factor (glum ) values is even highly demanded and considerably challenging. Here, an effective strategy is introduced to realize CP-OURTP with an emission decay time of 735 ms and a glum value up to 1.49, which exceeds two orders of magnitude larger than previous records, through a system composed of RTP polymers and chiral helical superstructures. The system exhibits excellent stability under multiple cycles of photoirradiation and thermal treatment, and is further employed for information encryption based on optical multiplexing. The results are anticipated to lay the foundation for the development of CP-OURTP materials in advanced photonic applications.

5.
Sci Rep ; 13(1): 16507, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37783721

RESUMO

In order to study the influence of structural parameters of porous gas bearing and operating parameters of linear compressor on the static and dynamic performance of porous gas bearing, based on gas lubrication theory, Darcy's law and Reynolds equation, the mathematical model and simulation model of porous gas bearing of linear compressor are derived and established. The static and dynamic characteristics of the porous gas bearing of the linear compressor are studied by using Fluent software simulation. According to the simulation results, the effects of inlet pressure, porous material thickness and gas gap on the gas consumption and bearing capacity of the porous gas bearing under different eccentricities are analyzed. The results show that the higher the inlet pressure is, the larger the gas consumption and bearing capacity; the thicker the porous material is, the smaller the gas consumption and the larger the bearing capacity, the thicker the gas gap is, the larger the gas consumption and the smaller the bearing capacity. On the basis of simulation research, considering the difficulties of processing and assembly, multi-objective optimization of porous gas bearings is carried out based on response surface methodology. Taking the bearing capacity and gas consumption as the objective functions, the intake pressure is set between 0.3 and 0.5 MPa, the thickness of porous materials is set between 3 and 5 mm, and the thickness of gas gaps is set between 10 and 20 µm. While ensuring the stable operation of the linear compressor, the optimal combination of design parameters is provided for the optimal design of gas bearings used in linear compressors.

6.
Front Plant Sci ; 14: 1285682, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37818322
7.
Chemphyschem ; 24(23): e202300320, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37743701

RESUMO

Paraffin (PA)/expanded graphite (EG) is an important composite phase change material with low cost, high heat storage, good thermal conductivity and cycling stability. Its thermal conductivity needs to be further improved for application in the thermal management system of power lithium-ion batteries. In this paper, copper plated expanded graphite (CPEG) with 3D porous structure was prepared by electroless copper plating method, which was used as thermal conductivity enhancing material to replace part of EG in PA/EG composite materials. For the optimized phase change material composed of 80 %PA-14 %EG-6 %CPEG, the copper content is very low (0.768 wt %), but its thermal conductivity can be significantly improved without loss of latent heat and thermal cycling stability. Its thermal conductivity is increased from 11 times to 16.5 times that of paraffin while compared with the copper-free composite material (80 %PA-20 %EG). The PA/EG/CPEG composite material exhibits good temperature control effect on power lithium-ion batteries.

8.
Chem Asian J ; 18(21): e202300708, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37712901

RESUMO

Achieving effective manipulation of emission color in photoresponsive materials is crucial for various advanced photonic applications. In this study, we designed and synthesized a hydrazone compound 1, ethyl (Z)-2-(2-([2,2':6',2''-terpyridin]-4'-yl)hydrazineylidene)-2-(4-(diphenylamino)phenyl)acetate, which possesses a push-pull structure incorporating triphenylamine and terpyridine. The emission intensity of compound 1 can be repeatedly switched "off" and "on" by irradiation with visible light and UV light, which induces the isomerization transition between the Z and E forms. In addition, compound 1 is capable of changing its emission wavelength from 540 nm to 607 nm through coordination with different zinc salts in toluene/CH2 Cl2 mixture (v : v=1 : 1). Importantly, we have successfully achieved dynamic manipulation of fluorescence color and intensity by altering the counterions of zinc complexes and switching the isomer from Z to E. Moreover, both compound 1 and its zinc complexes demonstrate remarkable photoswitchable properties with different fluorescence colors in the thin films. Finally, these films with various fluorescence colors were used for the production of luminescent tags.

10.
Inflammopharmacology ; 31(5): 2401-2410, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37646897

RESUMO

BACKGROUND: QP001, a novel meloxicam formulation, has been developed to manage moderate to severe postoperative pain. This study aimed to evaluate the efficacy and safety of QP001 injections for moderate to severe pain following abdominal surgery. METHOD: This prospective, multicenter, randomized, double-blind, placebo-controlled clinical trial enlisted patients experiencing moderate to severe pain following abdominal surgery. These patients were randomized to receive either QP001 injections (30 mg or 60 mg) or a placebo pre-surgery. The primary efficacy endpoint was the total morphine consumption within 24 h after the first administration. RESULTS: A total of 108 patients were enrolled, and 106 patients completed the study. The total morphine consumption in the QP001 30 mg group and 60 mg group, versus placebo group, were significantly lower over the following 24 h (5.11[5.46] vs 8.86[7.67], P = 0.011; 3.11[3.08] vs 8.86[7.67], P < 0.001), respectively. The total morphine consumption in the QP001 30 mg and 60 mg groups, versus placebo group, was also significantly decreased over the following 48 h, including the 24-48 h period (P ≤ 0.001). The QP001 30 mg and 60 mg groups, versus placebo, showed a significant decrease in the area under the curve for pain intensity-time as well as a significant decrease in the effective pressing times of the analgesic pump over the 24 h and 48 h periods (P < 0.05). The QP001 groups, versus placebo, show no significant different in Adverse Events or Adverse Drug Reactions (P > 0.05). CONCLUSION: Preoperative/preemptive QP001 provides analgesia and reduces opioid consumption in patients with moderate to severe pain following abdominal surgery, while maintaining a favorable safety profile.


Assuntos
Analgesia , Analgésicos Opioides , Humanos , Analgésicos Opioides/efeitos adversos , Meloxicam/uso terapêutico , Estudos Prospectivos , Morfina/efeitos adversos , Dor Pós-Operatória/tratamento farmacológico
11.
Am J Transl Res ; 15(5): 3442-3450, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37303633

RESUMO

OBJECTIVE: To investigate the efficacy of neurointervention combined with intravenous thrombolysis in ischemic stroke patients and the risk factors affecting cognitive function recovery. METHODS: A total of 114 patients with acute ischemic stroke (AIS) treated in Baoji People's Hospital from January 2017 to December 2020 were retrospectively selected and divided into an observation group and a control group according to different treatment methods. The observation group was treated with neurointervention + intravenous thrombolysis (n = 64), and the control group underwent intravenous thrombolysis (n = 50). The efficacy, recanalization rate, incidence of adverse events, National Institutes of Health Stroke Scale (NIHSS) score, Mini-Mental State Examination (MMSE) score and modified Rankin Scale (mRS) score were evaluated and compared between the two groups. Patients were further divided into a cognitive dysfunction group and a non-disorder group according the MMSE score after treatment, and logistics regression was used to analyze the risk factors of cognitive dysfunction. RESULTS: The overall response rate and the total recanalization rate of the observation group were significantly higher than those of the control group (both P < 0.05). Compared with those before operation, the NIHSS score at 7 d after operation and the mRS score 3 months after operation decreased, while the MMSE score increased in both groups (P < 0.05). The postoperative NIHSS score and mRS score were lower and MMSE score was higher in the observation group than those in the control group (P < 0.05). No significant difference was identified in the incidence of adverse events between the two groups (P > 0.05). Logistics regression analysis revealed that age, diabetes mellitus, hyperlipidemia and lesions at critical sites were independent risk factors for cognitive impairment in patients with AIS. CONCLUSION: Interventional thrombectomy combined with intravenous thrombolysis is effective in the treatment of cerebral infarction. This regimen can reduce neurological deficits and improve the recanalization rate. In addition, age, diabetes, hyperlipidemia and lesions at critical sites are independent risk factors for the development of cognitive impairment in AIS patients.

12.
Cancer Biomark ; 37(1): 39-52, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37005877

RESUMO

OBJECTIVE: This study attempts to investigate whether hsa_circRNA_001859 (circ_001859) could regulate the proliferation and invasion of pancreatic cancer through the miR-21-5p/SLC38A2 pathway. METHODS: GSE79634 microarray was analyzed with R package. The expression of circ_001859 in pancreatic cancer tissues and cells was verified by qRT-PCR. After the overexpression of circ_001859, cell proliferation, cell migration and invasion were verified by colony formation and transwell assay. The targeting relationship between miR-21-5p and circ_001859 was predicted by TargetScan and was verified by dual luciferase reporter assay, RNA pull down and qRT-PCR. The effect of miR-21-5p on cell proliferation, migration and invasion were investigated by colony formation and transwell assay respectively. Similarly, the targeting relationship between miR-21-5p and SLC38A2 was predicted by TargetScan and was verified by dual luciferase reporter assay, western blot and qRT-PCR. The effect of SLC38A2 on cell proliferation was investigated by colony formation. RESULTS: Circ_001859 was lowly expressed in pancreatic cancer tissues and cells. In vitro assays showed that overexpression of circ_001859 could inhibit the proliferation, migration and invasion of pancreatic cancer. In addition, this effect was also confirmed in xenograft transplantation model. Circ_001859 could be bind to miR-21-5p and sponge its expression in pancreatic cancer cells. Overexpression of miR-21-5p enhanced the proliferation, migration and invasion ability of pancreatic cancer cells, while the inhibition of miR-21-5p expression suppressed these abilities. Moreover, miR-21-5p directly targeted at SLC38A2 and inhibited SLC38A2 expression levels while circ_001859 up-regulated SLC38A2 levels. SLC38A2 expression knockdown enhanced cell proliferation but SLC38A2 overexpression resulted in decreased proliferation, and effects of SLC38A2 could be rescued by miR-21-5p and circ_001859. In addition, both QRT-PCR and immunofluorescence confirmed that circ_001859 could regulate tumor epithelial-mesenchymal transition (EMT) through the miR-21-5p/SLC38A2 pathway. CONCLUSIONS: This study suggests that circ_001859 may inhibit the proliferation, invasion and EMT of pancreatic cancer through the miR-21-5p/SLC38A2 pathway.


Assuntos
MicroRNAs , Neoplasias Pancreáticas , Humanos , RNA Circular/genética , Transição Epitelial-Mesenquimal/genética , Neoplasias Pancreáticas/genética , Proliferação de Células/genética , MicroRNAs/genética , Linhagem Celular Tumoral , Sistema A de Transporte de Aminoácidos , Neoplasias Pancreáticas
13.
Front Microbiol ; 14: 1141585, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37007500

RESUMO

Plant-associated microorganisms are believed to be part of the so-called extended plant phenotypes, affecting plant growth and health. Understanding how plant-associated microorganisms respond to pathogen invasion is crucial to controlling plant diseases through microbiome manipulation. In this study, healthy and diseased (bacterial wilt disease, BWD) tomato (Solanum lycopersicum L.) plants were harvested, and variations in the rhizosphere and root endosphere microbial communities were subsequently investigated using amplicon and shotgun metagenome sequencing. BWD led to a significant increase in rhizosphere bacterial diversity in the rhizosphere but reduced bacterial diversity in the root endosphere. The ecological null model indicated that BWD enhanced the bacterial deterministic processes in both the rhizosphere and root endosphere. Network analysis showed that microbial co-occurrence complexity was increased in BWD-infected plants. Moreover, higher universal ecological dynamics of microbial communities were observed in the diseased rhizosphere. Metagenomic analysis revealed the enrichment of more functional gene pathways in the infected rhizosphere. More importantly, when tomato plants were infected with BWD, some plant-harmful pathways such as quorum sensing were significantly enriched, while some plant-beneficial pathways such as streptomycin biosynthesis were depleted. These findings broaden the understanding of plant-microbiome interactions and provide new clues to the underlying mechanism behind the interaction between the plant microbiome and BWD.

14.
Sensors (Basel) ; 23(4)2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36850834

RESUMO

Iris recognition has been considered as one of the most accurate and reliable biometric technologies, and it is widely used in security applications. Iris segmentation and iris localization, as important preprocessing tasks for iris biometrics, jointly determine the valid iris part of the input eye image; however, iris images that have been captured in user non-cooperative and visible illumination environments often suffer from adverse noise (e.g., light reflection, blurring, and glasses occlusion), which challenges many existing segmentation-based parameter-fitting localization methods. To address this problem, we propose a novel double-center-based end-to-end iris localization and segmentation network. Different from many previous iris localization methods, which use massive post-process methods (e.g., integro-differential operator-based or circular Hough transforms-based) on iris or contour mask to fit the inner and outer circles, our method directly predicts the inner and outer circles of the iris on the feature map. In our method, an anchor-free center-based double-circle iris-localization network and an iris mask segmentation module are designed to directly detect the circle boundary of the pupil and iris, and segment the iris region in an end-to-end framework. To facilitate efficient training, we propose a concentric sampling strategy according to the center distribution of the inner and outer iris circles. Extensive experiments on the four challenging iris data sets show that our method achieves excellent iris-localization performance; in particular, it achieves 84.02% box IoU and 89.15% mask IoU on NICE-II. On the three sub-datasets of MICHE, our method achieves 74.06% average box IoU, surpassing the existing methods by 4.64%.

15.
Nat Commun ; 14(1): 627, 2023 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-36746937

RESUMO

Organic room-temperature phosphorescent (RTP) materials exhibiting reversible changes in optical properties upon exposure to external stimuli have shown great potential in diverse optoelectronic fields. Particularly, dynamic manipulation of response behaviors for such materials is of fundamental significance, but it remains a formidable challenge. Herein, a series of RTP polymers were prepared by incorporating phosphorescent rotors into polymer backbone, and these materials show color-tunable persistent luminescence upon excitation at different wavelengths. Experimental results and theoretical calculations revealed that the various molecular conformations of monomers are responsible for the excitation wavelength-dependent (Ex-De) RTP behavior. Impressively, after gaining insights into the underlying mechanism, dynamic control of Ex-De RTP behavior was achieved through thermal energy driven molecular rotations of monomers. Eventually, we demonstrate the practical applications of these amorphous polymers in anti-counterfeiting areas. These findings open new opportunities for the control of response behaviors of smart-responsive RTP materials through external stimuli rather than conventional covalent modification method.

16.
Chem Commun (Camb) ; 59(10): 1349-1352, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36648255

RESUMO

The effects of atmosphere and temperature on the electrochemical reversibility of black phosphorus (BP) anodes were investigated. BP anodes prepared in ambient air exhibited much-enhanced electrochemical activity due to the newly formed Cu3P phase. This work highlights the importance of maintaining intragranular electronic conduction for developing advanced BP-based anodes with high reversible capacities.

17.
J Agric Food Chem ; 71(4): 1957-1969, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36688926

RESUMO

Bacterial wilt caused by Ralstonia solanacearum (Rs) is one of the most important diseases found in ginger; however, the disease resistance mechanisms dependent on root bacteria and exudates are unclear. In the present study, we analyzed the changes in the composition of rhizobacteria, endobacteria, and root exudates during the pathogenesis of bacterial wilt using high-throughput sequencing and gas chromatography-mass spectrometry (GC-MS). Rs caused bacterial wilt in ginger with an incidence of 50.00% and changed the bacterial community composition in both endosphere and rhizosphere. It significantly reduced bacterial α-diversity but increased the abundance of beneficial and stress-tolerant bacteria, such as Lysobacter, Ramlibacter, Pseudomonas, and Azospirillum. Moreover, the change in rhizobacterial composition induced the changes in endobacterial and root exudate compositions. Moreover, the upregulated exudates inhibited ginger bacterial wilt, with the initial disease index (77.50%) being reduced to 40.00%, suggesting that ginger secretes antibacterial compounds for defense against bacterial pathogens.


Assuntos
Ralstonia solanacearum , Zingiber officinale , Bactérias , Doenças das Plantas/microbiologia
18.
Neural Netw ; 160: 175-191, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36657331

RESUMO

Under the persistent excitation (PE) condition, the real dynamics of the nonlinear system can be obtained through the deterministic learning-based radial basis function neural network (RBFNN) control. However, in this scheme, the learning speed and accuracy are limited by the tradeoff between the PE levels and the approximation capabilities of the neural network (NN). Inspired by the frequency domain phase compensation of linear time-invariant (LTI) systems, this paper presents an adaptive phase compensator employing the pure time delay to improve the performance of the deterministic learning-based adaptive feedforward control with the reference input known a priori. When the adaptive phase compensation is applied to the hidden layer of the RBFNN, the nonlinear approximation capability of the RBFNN is effectively improved such that both the learning performance (learning speed and accuracy) and the control performance of the deterministic learning-based control scheme are improved. Theoretical analysis is conducted to prove the stability of the proposed learning control scheme for a class of systems which are affine in the control. Simulation studies demonstrate the effectiveness of the proposed phase compensation method.


Assuntos
Algoritmos , Dinâmica não Linear , Retroalimentação , Redes Neurais de Computação , Aprendizagem
19.
Anal Bioanal Chem ; 415(2): 345-356, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36350342

RESUMO

Bear bile powder (BBP) is one of the most famous traditional Chinese medicines derived from animals. It has a long history of medicinal use and is widely used in the treatment of hepatobiliary and ophthalmic diseases. Due to its similar morphological characterizations and chemical composition compared with other bile powders, it is difficult to accurately identify its authenticity. In addition, there are very few methods that could analyze the geographical origins of BBP. In this study, elemental analysis isotope ratio mass spectrometry (EA-IRMS) and inductively coupled plasma mass spectrometry (ICP-MS) were used to determine stable isotope ratios and elemental contents, respectively. Combined these variables with chemometrics, the discrimination models were established successfully for identifying the authenticity and geographical origins of BBP. Meanwhile, the discrimination markers were identified by calculating the variable importance for the projection (VIP) value of each variable. A total of 13 discrimination markers (δ13C, δ15N, C, Li, Mg, K, Ca, Cr, Ni, Zn, As, Se, and Sr) were used to further establish the fingerprint of BBP. According to similarity analysis, the authenticity and geographical origins of BBP could be identified without chemometrics. In conclusion, the present study established a reliable method for authenticity identification and origin traceability of BBP, which will provide references for the quality control of bile medicines.


Assuntos
Ursidae , Animais , Pós , Bile , Isótopos/química , Espectrometria de Massas/métodos
20.
ACS Omega ; 7(43): 39206-39213, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36340145

RESUMO

This study aimed to identify Velvet antler and its counterfeits and to further evaluate their quality. Mitochondrial cytochrome b (Cytb) was used as a target gene to identify Velvet antler samples, and a DNA barcoding method was established for species origin identification in Velvet antlers. After identification, the stable isotope contents and ratios were adopted to evaluate the quality of different specifications of authentic Velvet antler in combination with chemometrics. Two stable isotope contents (C % and N %) and ratios (δ13C and δ15N) in three kinds of Velvet antler slices of different specifications, namely, wax slices, powder slices, and bone slices, were determined. Nine Velvet antler samples sold in the market were identified for label conformity. Only two samples were consistent with the labeled species, and the others were counterfeits. The three slices of Velvet antler of different specifications were clearly distinguished by principal component analysis and hierarchical cluster analysis. Then, the discriminant model of partial least squares discriminant analysis was established, and 100% discrimination accuracy was observed in this model. All the Velvet antler slice samples of different specification samples were grouped clearly according to their sources. In summary, it is feasible for the identification and quality grade evaluation of Velvet antler by DNA barcoding based on mitochondrial Cytb and stable isotope techniques combined with chemometric analysis. The establishment of this method also provided a reference for the evaluation of other animal-derived medicinal materials.

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